Improvement in oscillating engines



UNITED 'STILITES PATENT OEEIcEf WILLIAM E. BIRD, OF NEW YORK, N. Y.

IMPROVEMENT IN OSCILLATING ENGINES.

Specification forming part of Letters Patent No. 64,940, dated May 21, 1867.

To all whom it 'may concern Be it known that I, WILLIAM E. BIRD, of

l the city, county, and State of New York, have invented a certain new useful Improvement on Steanr and other Oscillating En gines, of which the following is a full, clear, and exact description, reference being had to the accompanying drawing, forming a part of this speciiication, and in which- Figures 1 and 2 represent longitudinal views, at rightfangles to each other, of an oscillatin g steam-engine with my improvement applied to it; and Fig. 3, aface view ofthe end of the engine-trunnion and annular projection of the valve-seat, which fits therein, showing' the ports or passages thereof.

Like letters indicate corresponding parts.

One great objection which has frequently been raised to oscillating engines is the working of the valve as' usually applied to the trunnion of the engine. Not only has there been a want of steadiness in the driving ofthe valve occasioned by its immediate connection or contact witl the oscillating trunnion, but a great difficulty in keeping the valve steam-tight,

which difliculty is generally increased by the peculiar construction or shape of the valve, that, where of disk form and vibrating from a central or other axis, travels on its rubbingsurface with an unequal velocity against its seat, the speed being greater and increasing toward the circumference, and wear consequently more excessive, than at or toward the center, where the velocity is less. This ineqality of rubbing action, combined with absence of a xed or stationary and steady valve-seat, has made it almost impossible to keep the valve close circumferentially, even thoughtightlyscrewing it down, which induces excessive friction.

My improvement aims at obviating these difficulties in a simple and practicable manner 5 and the nature of the inventionconsists in a novel combination, with the trunnion of such engines, of an ordinary or other suitable reciprocating slide-valve, having an equality of travel on its surface, and working against a stationary and steady seat.

Referring to the accompanying drawing, A represents the bed-plate of an oscillating engine, and B and C uprights and standards'for support of the trunnions a of the cylinder D and driving-shaft E of the engine. 'F is the f piston-rod, G the driving-crank, and H the eccentric for operating the valve. Bolted inl which seat and the trunnion are passages d d,

commimicating with ways e to opposite' ends of the cylinder. f is the exhaust port or passage, and g the steam-inlet to the valve-box.

The valve J is or may be an ordinary D or i other slide-valve, serving', as it is reciprocated in a rectilinear direction by the rod h of the eccentric H or other driving device, to alter nately open the passages d to the steam-space of the valvebox and exhaust-passagef, and so keep up the requisite reciprocating action of the. enginepiston. .By this combination of aslide-valve with one of the trunnions of the vengine-cylinder, the liability to leakage and amount of friction 'is reduced, and a simple and steady action of the valve against a fixed or stationary seat, with equality of wear on its rubbing face or surface, secured.

It is important, in order to secure a proper working action, thatthe ports or passages d d, in either the face end of the trunnion or exterior end of the ann ular proj ection b of the valve-seat,

should exceed in width that required for fixed communication between such passages of the ports during the entire oscillating motion of the trunnion; thus said passages are made Wider in the trunnion than in the projection b, as represented in Fig. 3 of the drawing.

What I claim as new and useful, andl desire to secure by Letters Patent, is-l The combination,'in steam or other oscillating engines, with the trunnion of the enginecylinder, of a reciprocating slide-valve work ing against a fixed or stationary seat, and operating to control the ports or passages of the engine, substantially as described.

WM. E. BIRD.

Witnesses J. W. CooMBs, G. W. REED. 

